The idea they have that they can charge people for videos of them playing games or talking about games when its free all over the internet. The premium shit is basically the xbox live gold of videogame websites. It is extremely greasy that they take advantage of the people that love them enough to give them money. Also the fact that they will make t shirts as soon as a stupid meme comes about in order to squeeze more out of those people.
So... you feel bad for people who choose to support a website they like? You're acting like those people don't have a choice in how they spend their money. People love buying t-shirts of stuff they support.
Giantbomb is a business, get over it man. They still put out hundreds of videos a year for free. Not to mention they host a huge database for everybody to use. Not greasy at all.